Bottom Line:
A case of malignant mesenchymoma of the bladder containing leiomyosarcoma, rhabdomyosarcoma, chondrosarcoma, osteosarcoma, and myxomatous components is described.The primary pedunculated tumor measuring 14×13×7 cm and weighing 343 g arose from the left trigone of the bladder and was treated by total cystectomy.Herein, we present the fifth case of malignant mesenchymoma of the urinary bladder to be reported in the literature, which presented five unrelated differentiated tissues more than did previously reported cases.

ABSTRACTA case of malignant mesenchymoma of the bladder containing leiomyosarcoma, rhabdomyosarcoma, chondrosarcoma, osteosarcoma, and myxomatous components is described. The primary pedunculated tumor measuring 14×13×7 cm and weighing 343 g arose from the left trigone of the bladder and was treated by total cystectomy. The histogenesis of malignant mesenchymomas and their optimal management strategy and prognosis remain uncertain. Herein, we present the fifth case of malignant mesenchymoma of the urinary bladder to be reported in the literature, which presented five unrelated differentiated tissues more than did previously reported cases.

Figure 1: (A) Magnetic resonance imaging (MRI) of the pelvis demonstrated a large mass in the urinary bladder that shows focal contrast medium enhancement on the left side with adjacent vesical wall thickening and obliteration of the lower signal intensity on T2WI. (B) Macroscopically, the urinary bladder contained a nonencapsulated, huge, and lobular mass, which was located in the left trigone and measured 14 × 13 × 7 cm in size. (C) and (D) On the cut surface, this tumor was composed of a predominant white, myofibrous-like component, and myxomatous (asterisk), hemorrhage, and tumor necrosis foci. Several hard osteochondroid-like nodules were also palpable within this tumor (arrow).

Mentions:
Magnetic resonance imaging (MRI) of the pelvis demonstrated a large mass in the urinary bladder. The mass shows focal contrast medium enhancement on the left side with adjacent vesical wall thickening and obliteration of the lower signal intensity on T2WI (Figure 1A). Urinary bladder malignancy was suspected, and the differential diagnoses included urothelial cell carcinoma with blood clot, sarcoma, or other benign neoplastic mass.

Figure 1: (A) Magnetic resonance imaging (MRI) of the pelvis demonstrated a large mass in the urinary bladder that shows focal contrast medium enhancement on the left side with adjacent vesical wall thickening and obliteration of the lower signal intensity on T2WI. (B) Macroscopically, the urinary bladder contained a nonencapsulated, huge, and lobular mass, which was located in the left trigone and measured 14 × 13 × 7 cm in size. (C) and (D) On the cut surface, this tumor was composed of a predominant white, myofibrous-like component, and myxomatous (asterisk), hemorrhage, and tumor necrosis foci. Several hard osteochondroid-like nodules were also palpable within this tumor (arrow).

Mentions:
Magnetic resonance imaging (MRI) of the pelvis demonstrated a large mass in the urinary bladder. The mass shows focal contrast medium enhancement on the left side with adjacent vesical wall thickening and obliteration of the lower signal intensity on T2WI (Figure 1A). Urinary bladder malignancy was suspected, and the differential diagnoses included urothelial cell carcinoma with blood clot, sarcoma, or other benign neoplastic mass.

Bottom Line:
A case of malignant mesenchymoma of the bladder containing leiomyosarcoma, rhabdomyosarcoma, chondrosarcoma, osteosarcoma, and myxomatous components is described.The primary pedunculated tumor measuring 14×13×7 cm and weighing 343 g arose from the left trigone of the bladder and was treated by total cystectomy.Herein, we present the fifth case of malignant mesenchymoma of the urinary bladder to be reported in the literature, which presented five unrelated differentiated tissues more than did previously reported cases.

ABSTRACTA case of malignant mesenchymoma of the bladder containing leiomyosarcoma, rhabdomyosarcoma, chondrosarcoma, osteosarcoma, and myxomatous components is described. The primary pedunculated tumor measuring 14×13×7 cm and weighing 343 g arose from the left trigone of the bladder and was treated by total cystectomy. The histogenesis of malignant mesenchymomas and their optimal management strategy and prognosis remain uncertain. Herein, we present the fifth case of malignant mesenchymoma of the urinary bladder to be reported in the literature, which presented five unrelated differentiated tissues more than did previously reported cases.